The Esbats are the Wiccan Full Moon Celebrations.
At this time we gather to worship She Who Is.
There are 12 - 13 Full Moons yearly, or one every 28.1/4 days.
The Moon is symbolic of the Goddess, as well as a source of energy.
Each Moon has a traditional name.

Each Full Moon has a different meaning and magickal purpose. Because of this, it is a good idea to plan your Full Moon Rituals to work with the meaning and purpose of the Moon. The Full Moon is also a traditional time for divinations of all kinds, as the power of the Moon aids in such work.

January - Wolf Moon Plan a ritual of protection around your home and family.
February - Storm Moon Plan a ritual to ask the Old Ones for help in planning your future.
March - Chaste Moon Plan a ritual to help fulfill your wishes is appropriate.
April - Seed Moon Plan a ritual to physically plant your seeds of desire in Mother Earth.
May - Hare Moon Plan a ritual to reaffirm your goals.
June - Dyad (pair) Moon Plan a ritual to balance your spiritual and physical desires.
July - Mead Moon Plan a ritual to decide what you will do once your goals have been met.
August - Wyrt (green plant) Moon Plan a ritual to preserve what you already have.
September - Barley Moon Plan a ritual of Thanksgiving for all the Old Ones have given you.
October - Blood Moon Plan a ritual to remember those who have passed from this world, and be sure to make an offering to them.
November - Snow Moon Plan for a ritual to work on ridding yourself of negative thoughts and vibrations.
December - Oak Moon Plan for a ritual to help you remain steadfast in your convictions.

A Blue Moon is variable and occurs when the Moon with it's 28 day cycle
appears twice within the same calendar month, due to that month's 31 day duration.

New Moon - Sometimes the moon phases are broken down further, where the new moon represents enchantments and temptations. These properties are also present at any other times during a lunar phase when the moon is unseen or clouded over.